A hemodialysis patient needs to be subjected to hemodialysis at a rate of 2 to 3 times a week. Every time the patient is subjected to dialysis, piercing into a blood vessel of the patient with a indwelling needle causes the patient to suffer considerable pain.
The applicant of the present invention has already proposed a device for forming a hole for inserting an indwelling needle (refer to Japanese Patent Laid-Open No. 176009/2000) for decreasing such puncture pain to a minimum level. The device has a distal end and a proximal end, and includes a hollow body having an inner cavity through which a guide wire can be inserted. At least the distal end portion of the device, which is inserted into a human body, is formed of a tubular body difficult to bend to or to be easily collapsed. A member for closing an opening portion of the cavity is detachably provided on the proximal end portion. After the device is indwelt for several days in a location extending from the surface of the skin to a blood vessel, a hole serving as a passage for inserting an indwelling needle is formed. In order to conduct hemodialysis, an indwelling needle is inserted into the hole, so that the puncture pain which the patient subjected to hemodialysis suffers is substantially alleviated.
However, in order to indwell the device for forming a hole for inserting an indwelling needle in a human body, the following complicated operations have been needed.    (1) After a general indwelling needle for dialysis comprising an inner needle and an outer needle is pierced into a shunt portion in a blood vessel of a patient, the inner needle is pulled out and the outer needle is indwelt in an inside of the blood vessel.    (2) A guide wire is then inserted into the outer needle and, thereafter, the outer needle is pulled out and the guide wire alone is indwelt inside of the blood vessel.    (3) A device for forming a hole for inserting an indwelling needle is introduced into the inside of the blood vessel along the guide wire and indwelt therein.
Such complicated operations for indwelling the device have been a considerable burden on medical personnel. Moreover, while the device for forming a hole for inserting an indwelling needle indwells in the human body, there is a risk that the device will hurt the wall of the blood vessel. Therefore, it is necessary for the patient to lie still. These problems make it difficult to indwell the device for forming a hole for inserting an indwelling needle into a patient for a long period of time.
The present invention has been made in view of the above-mentioned circumstances, and provides a device for forming a hole for inserting an indwelling needle capable of forming a hole very easily.